Operating mechanism for musical instruments.



PATENTED JULY 30, 1907. B.S.DEAN. OPERATING MECHANISM FOR MUSICAL INSTRUMENTS.

APPLIOATION FILED NOV 26, 1906.

BENJAMIN S. DEAN, OF SAN FRANCISCO, CALIFORNIA.

OPERATING MECHANISM FOR MUSICAL INSTRUMENTS.

Specification of Letters Patent.

Patented July 30, 1907.

Application filed November 25, 1905. Serial No. 288,988.

To all whom it may concern:

Be it known that I, BENJAMIN S. DEAN, a citizen of the United States of America, and a resident of San Francisco, county of San Francisco, State of California, have invented certain new and useful I1nprove-, ments in Operating Mechanism for Musical Instruments and Musical-Instrument Players, of which the following is a specification, reference being had to the accompanying drawings, forming a part thereof.

My invention relates to improvements in self-playing musical instruments and musical instrument players, and particularly to the operating mechanism employed for the production of individual tones.

The main objects of my invention are to produce a simple effective mechanism by which individual tones may be produced in instruments controlled by the movement of a perforated record sheet over a tracker board, whereby the mechanism, while simple and inexpensive to build, shall respond quickly and accurately when the perforations in the record sheet register with the corresponding perforations in the tracker board, and to improve and increase the delicacy of the so called touch of the instrument.

To these ends my invention consists in a novel combination of elements such as I will now proceed to describe.

In order that my invention may be fully understood I will describe the same in connection with an embodiment thereof illustrated in the accompanying drawing, and will then point out the novel features in claims.

The drawing is a view partly in side elevation and partly in vertical section of such portions of a musical instrument player as is necessary for the full understanding of my invention.

1 designates the ordinary or any desired form of tracker board, 2 a vacuum chamber, 3 a. primary pneumatic device, 4 a secondary pneumatic device, and 5 an operating lever or striker, such for instance as a piano player lever or other lever for controlling a musical instrument action. The usual, or any form of, record sheet 6 is arranged to travel over the tracker board 1, perforations therein being arranged to register with perforations in the tracker board, which form the termini of ducts or channels 7. There is at least one said duct or channel 7 for each tone to be produced, and at least one of the mechanisms in connection therewith which I will now describe. As the devices for producing all the tones may be of similar nature, the description of one will serve for a description of them all. The duct or channel 7 leads to a cross channel 8, arranged in open communication with the primary pneumatic device 3. This device comprises a cylinder 9 closed at its outer end and fitted upon a stationary piston 10. A stem 11 is secured to the cylinder 9, said stem arranged to penetrate through the vacuum chamber 2, and to carry valves 12 and 13. The stem 11 is loosely fitted in a channel 14, which leads from the vacuum chamber to the chamber inclosed between the head of the cylinder 9 and the end of the piston 10. The cross channel 8 communicates with the channel 14 intermediate its ends, the portion of the channel 14 from the cross over channel 8 to the vacuum chamber being commonly known as a bleeding port. A spring 15 may be employed to oppose inward movement of the cylinder 9, and to force outward movement thereof when the same is balanced as to atmospheric pressure. The valves 12 and 13 control, respectively, ports 16 and 17, the former opening to atmosphere and the latter into the vacuum chamber 2. Both of the ports communicate with a channel 18, which leads to a chamber 19 within the secondary pneumatic device 4. This device comprises cylinder 20, closed at its upper end, and a stationary piston 21. to which the cylinder is fitted. A portion of the channel 18 passes clear through the stationary piston 21 into the said chamber 19.

With the parts in their normal condition, vacuum in the chamber 2 will cause atmospheric pressure to press up the primary pneumatic device, so as to close the valve 12 under the port 17, and open the valve 13 from the port 16. This will hold the secondary pneumatic device normally open to atmosphere, as shown. When, however, air is vented into the channel 7 by reason of a perforation in the record sheet 6 coming in register therewith, air will be vented through the said channel into the cross over port 8, and into the primary pneu matic device 3. Air will be supplied to the said de vice quicker than it can be exhausted through the bleeding port, and the spring 15 will cause the cylinders 9 to move outward. This will open the valve 12 and close the valve 13, thus closing the channel 18 to atmosphere and opening it to vacuum. Atmospheric pressure will then immediately force the cylinder 20 of the secondary pneumatic device 4 downward, as will be well understood.

Connected to the cylinder 20 of the secondary pneumatic device 4 is a bell crank lever 22, one arm thereof being connected to the cylinder 20 by means of a stud 23. The other arm of the bell crank lever is connected by means of a link, wire, rod or cord 24 with a friction band 25, which surrounds the periphery of a disk or roller 26. The other end of the band 25 is connected by means of a link, wire, rod or cord 27 with one arm of a bell crank lever 28, the other arm of which is connected by means of a link 29 with the lever 5. The disk or roller 26 is arranged to rotate continuously in the direction of the arrow thereon, the friction band 25 being loosely supported thereby. Upon operation of the secondary pneumatic device 4 to rock the lever 22 upon its pivotal center, tension will be placed upon the connection 24 to tighten the band 25, so as to cause it to be carried round for a short distance With the disk or roller 26. This amount will be a distance suilicient to rock the bell crank28 and to depress the operating lever 5. A spring 30 may be conveniently employed for returning the parts to their normal position, and a stop 31 engaging the bell crank lever 22 will limit the movements of the parts. The foregoing comprises an exceedingly simple yet effective means for operating a musicalinstrument or musical instrument player and is particularly effective in connection With pianos or piano players. The pneumatic means, in combination with the friction band, comprises operating means which produce a delicate yet iirm touch. The parts respond very quickly to their control, and, being extremely light, have minimum of momentum and inertia; The simplicity of the device makes it inexpensive to build, and but very little likely to get out of order. If it should get out of order, the parts are all readily accessible for repair. The roll 26 may comprise a continuous roll extending the entire Width of the instrument, or it may comprise individual disks mounted upon a common shaft, as may be desired.

It will be obvious that the foregoing is but one embodiment of my invention, and that the same is capable of many and varied modifications within the spirit and scope of my invention, and, further, that certain parts may be employed in connection with other parts of different construction, hence I do not desire to be limited only to the precise details of construction and combination of parts herein.

What I claim is:

1. Mechanism of the class described comprising a continuously rotating roll, a friction band wrapped completely around the same and having its ends overlapping and pro ,iecting in opposite directions, pneumatic means for applying longitudinal tension to the said band connected to one of the projecting ends of the said band, and a striker con nected to the other projecting end of the said band.

2. Mechanism of the class described comprising a continuously rotating roll, a friction band wrapped around the same. a toneproducingmechanism operating-member connected to the said friction band at one end thereof, secondary pneumatic means connected with the band at the other end thereof arranged to apply longitudinal tension to the said band, and primary pneumatic means for controlling the secondary pneumatic means.

3. Mechanism of the class described comprising a continuously rotating roll, a friction band wrapped around the same, a striker connected to the friction band at one end, a secondary pneumatic means comprising a stationary piston and a spring-returned cylinder fitted thereto, said cylinder having a closed head and connected with the other end of said friction band, and primary pneumatic means for controlling the air pressure within said cylinder.

4. Mechanism of the class described comprising a continuously rotating roll, a friction band thereon, a striker connected with the band at one end thereof, and primary and secondary pneumatic means including a vacuum chamber, a stationary piston, a springreturned cylinder mounted upon said piston, said cylinder connected with the other end of said friction band, another stationary piston, a spring-returned cylinder having a closed end fitted thereon, said cylinder in open communication with said vacuum chamber, and valve means operated by said cylin der for opening and closing communication between said first named cylinder and the vacuum chamber and the atmosphere.

In mechanism of the class described, the combination with a continuously rotating roll, a friction band mounted thereon, and a striker connected with the said friction band at one end, of secondary pneumatic means connected with the said friction band at the other end, primary pneumatic means for controlling said secondary pneumatic means, and a tracker from which the said primary pneumatic means may be controlled, said primary and secondary pneumatic means comprising a vacuum chamber, primary and secondary stationary pistons having ports or passages therethrough arranged for connection with said vacuum chamber. spring-returned cylinders mounted on said pistons and having closed heads closing them to the atmosphere, a discharge port leading from the atmosphere to the passage which passes to the cylinder of the secondary pneumatic, a valve stem carried by the cylinder of the primary pneumatic, and two valves carried by the said stem, one of said valves controlling the said port, and the other of said valves controlling communication between the vacuum chamber and the passage leading through the said secondary piston to the cylinder thereon,

BENJAMIN SJDEAN.

Witnesses Enmcn'r WILLIAMsON, Gnonon A. Manon. 

